var provinceArr=['浙江','江苏','上海'];
var cityArr=[['杭州','宁波','温州','绍兴','台州'],
['南京','苏州','无锡','扬州'],
['黄埔区','浦东区','静安区']];
var province=document.getElementById('province');
var city=document.getElementById('city');
for(var i in provinceArr){
	var op=new Option(provinceArr[i],i);
	province.options.add(op);
}
province.onchange=function(){
	
		city.length=0;
var selected=province.value;
for (var j in cityArr[selected]) {
        var cs=new Option(cityArr[selected][j],j);
		city.options.add(cs);
	}
}
